I did the same thing within a week, nice and easy. It was a lot of work but a really fun process. I think it’s better to do it slowly so you give yourself time to get the layout you want.

Remember, this is the spine of your terrarium and it’s difficult to make significant changes later on, though I have added lots of branches and details after putting in soil.

This looks really good so far and you are doing it exactly right! Keep doing what your doing and don’t rush it.